Bomb releasing shackle



Oct. 15, 1946. R. l. MARKEY BOMB RELEASING SHACKLE Filed July 7, 1944 I INVENTOR Roscoe LMRRKEY,

ATTORNEY Oct. 15, 1946. I

R. MARKEY BOMB RELEASING SHACKLE Filed July 7, i944 sheets sheet 2 m INVENTOR RoscOE LMARKEY, BYg:

IVATTORNEY Patented Got. 15, 1946 UNITED STATES PATENT OFFICE Pollak Manufacturing Company,

Arlington,

N. 5., a corporation of New Jersey Application July 7, 1944, Serial No. 543,886

11 Claims.

The invention relates to bomb releasing shackles and has to do more particularly with a unit which carries the electrical mechanism for operating the bomb holding or supporting means of the shackle.

One of the objects of the invention is to provide a simple compact and fool-proof unit for attachment to a bomb shackle or rack, the unit containing all the electrical mechanism for operating the mechanical parts of the shackle or rack to release the bomb.

Another important object is to provide a unit in which the operating or movable parts directly motivated by the electrical operating means are statically balanced thus resulting in ease of operation and the consumption of a minimum amount of current.

Another object is to provide a unit in which the parts are so arranged as to develop a minimum amount of friction during their actuation and operation thus insuring more accurate functioning, prolonging the life of the device and substantially decreasing the amount of current needed, particularly for initial operation,

Still another object is the provision of a unit which is moisture proof and substantially air tight thus guaranteeing the operation regardless of weather or atmospheric conditions.

Another object is the provision of improved simplified means whereby the circuit to the tolltale light in the bombardiers station is broken after a bomb has been dropped from its respective shackle and at the same time a circuit is prepared, which when completed, will permit of a bomb being released from an adjourning station.

It will be understood that the foregoing general description and the following detailed description are exemplary and explanatory of the invention but are not restrictive thereof. In addition to the foregoing other objects and advantages will become apparent as this specification proceeds. Referring to the drawings forming a part thereof and in which one embodiment of the invention is illustrated:

Fig. 1 is an elevational view looking toward the rear of the control unit and part of the shackle being indicated in broken lines;

Fig. 2 is a top plan view;

Fig. 3 is an end view, the shaclde being in section;

Fig. 4 is an elevational view of the control unit taken on a larger scale and with the cover removed;

Fig, 5 is fragmentary detail sectional plan view taken on the line 55 of Fig. 4;

Fig. 6 is a cross sectional view on line 66 of Fig. 4; and

Fig. '7 is a fragmentary elevational sectional view taken in the same plane as Fig. 4 with the parts in a different position, and taken on the line 'i? of Fig. 5.

The present application relates to similar subject matter to that disclosed in copending application, Serial No. 515,590, filed December 24, 1943. In that application, as in the present one, a removable control unit carrying all the electrical operating means was disclosed. Said pending application and the present application have to do with improvements disclosed in Patent No. 2,344,211 dated March 14, 1944. Referring again to the drawings, a shackle is shown similar to that disclosed in the patent to Markey, No. 2,298,360, dated September 22, 1942.

A framework or supporting structure It) has hinge members ll resistance welded or otherwise secured to either end thereof. The upper parts of the hinge-members .support the shackle in its rack or hanger and hooks l2 are pivoted at l3 in the lower parts of th hinge-members. The hooks l? in the locked position of the shackle as shown in Fig. 1 close the entrances of openings Hi and support rings or other suitable members l5 which carry the bomb (not shown),

Theupper portions of the hooks l2 are pivoted at it to a longitudinally extending tie member ll. It will be apparent the hooks l2 and tie member ll are movable simultaneousl and furthermore the weight of the bomb as it is suspended from the hooks will urge the tie member and its hooks to bomb releasing position,

One of the hooks l2 has an extending toe l8 which engages a notch [Sin a lever 20 when the parts are in the locked position of Fig. l. The lever 2% is pivoted at 25 and it will be obvious when this lever is moved to the right in Fig. 1, either manually or by electrically operated means, the end ofthe toe l8 will move awa from the notch la and the bomb will be dropped.

The control unit comprise a box-like casing 25 having a cover 26 secured thereto by bolts 21. A gasket 28 is interposed between the walls of the casing and the cover, the gasket functioning to insure the interior of the casing being moisture proof and substantially airtight. The casing houses the releasing magnet,'the mechanism operated thereby, the switches and wiring. If desired as in the aforesaid mentioned application,

3 Serial No. 515,590, arming units may be mounted on the bottom or exposed face of the casing.

The control unit may be detachably secured to the shackle in numerous ways, the particular method illustrated forming no part of the present invention. As shown a shouldered pin 30 is mounted in an ear 3| depending from the lower part of the casing. Secured to the inner end of the pin 30 is an arm 32 which has a socket taking over the protruding head of the pin 2| upon which the lever is pivoted. The pin has a knob 34 on its outer end and a spring engages this knob to urge the pin 30 and its arm 32 to holding position. When it is desired to remove the control unit from the shackle the knob 34 is depressed to cause the socket in the arm to become disengaged from the head of the pin 2| and the arm is rotated to move it from the under side of the shackle frame.

To properly position the control unit on the shackle in relation to the lever 20 a projecting end of pin 2| engages a recessed screw head 35 which is preferably formed on one of the screws 1 utilized to secure the cover 26 in place. To further insure against any upward displacement or canting of the control unit a fixed stud 31 carried by another ear 38 depending from the casing engages the lower edge of one of the shackle side plates.

To complete the detachable securing means a spring clip 39 is secured to the cover or rear of the control unit at the upper part thereof and the spring clip has a pair of fingers 40 extending over, and gripping the rear plate of the shackle frame and another finger 4| which rests upon or engages the connecting portion of the shackle frame plates.

A cable 42 carries all of the electrical connections into the control unit. In order to obviate confusion in the drawing the various electrical connections 43 are broken away immediately upon their entrance into the casing as shown in Fig. 4. It is to be understood they will lead to the magnet and various switches, hereinafter described, in the conventional manner. As the electrical circuits are substantially the same as illustrated in the wiring diagram of my aforesaid mentioned pending application, Serial No. 515,590, reference may be had to said diagram.

A clip 44 is secured to the cable just outside of the casing and a bracket 45 welded or otherwise fast to the clip is secured at 46 to the casing. This arrangement relieves strains on the cable and insures against the withdrawal of the cable from the casing when the control unit'or the control unit and the shackle may be carried by the cable alone, such for instance as when the supply of bombs is being replenished. The cable leads to a conventional disconnect plug ,(not shown) which if desired might be secured to the casing 25 It will be apparent that a control unit is thus provided which may be instantly attached to or detached from the shackle. When the shackle is removed from the control unit to apply it to another bomb the control unit remains suspended from the cable 42. Obviously the cable connecting means might be widely varied.

The full line position of Fig. 14 illustrates the parts of the control unit for operating the bomb releasing mechanism in the position they would assume when the shackle mechanism is in bomb supporting position. An electro-magnet 50 is carried in the casing 25 by a pair of brackets 5| secured by screws 52 to a boss 53 formed integral with. the casing. The winding of the electro- 4 magnet is designated by the reference numeral- 54 and its core by the numeral 55.

Pivoted at 50 and 5'! are a pair of hell crank levers 58 and 59 both under the influence of the electro-magnet. As illustrated the bell crank levers are formed of laminations to provide a better path or circuit for the magnetic flux and as particularly shown in Figs. 4 and 5 the laminations are secured together by peened over pins 60.

The levers are arranged so they will function in absolute unison with each other or to all intents and purposes as a single unit and yet have a toggle like action with the practical elimination of friction. The inner adjacent ends of the horizontal arms 62 of the bell crank levers are bifurcated or provided with semi-circular indentations 63 which cooperate with a headed stud 54.

The head 65 of the stud 64 is loosely confined between the ends of the levers and a spacer plate 56 -which rests against the inside of the cover 25.

Thus what might be termed a floating anti-frictional pivotal connection is formed between the adjacent ends of the arms 62 of the bell crank levers. In addition this arrangement of levers provides for a means of positively connecting magnetic forces in a linkage to release the pawl 25.

One of the important aspects of the present invention is the fact that the two levers 58 and 59 when connected by the stud 64 are statically balanced in relation to each other, and in relation to their pivots or in other words when they are in their normal position or the full line position of Fig. 4 they are in a state of equilibrium. Thus when the magnet is energized and the levers are attracted there is positively no gravitational weight to overcome. Therefore the magnet may be comparatively quite small and light weight in construction in consideration of the work to be accomplished, that is releasing the mechanism to drop a bomb of 1000 pounds or more. Another beneficial advantage of the statically balanced levers is that a minimum amount of current is needed to energize the magnet and attract the levers and in addition the mechanism functions to prevent external forces from accidentally releasing the bomb. The studs 55 and 51 upon which the levers are pivoted are advantageously mounted in bosses 6| formed on the, bottom wall of the casing as shown in Fig. 5.

The spacer plate 66 has a pair of cup-shaped portions 61 found on either end thereof and provided with apertures into which the pivotal studs 56 and 5'! are entered. The bell crank levers are loosely confined between the bosses 6| and the portions 61 thus providing for free pivots and preventing endwise displacement of the levers in relation to the studs. The spacer plate 66 thus serves a dual purpose, that is maintaining the headed stud 64 in position as well as the levers 58 and 59, no screw threads or nuts being required to form the pivots.

The bell crank levers 58 and 59 have vertically or upwardly extending arms 68 and 69 which function as armatures for the electro-magnet. A laterally extending toe 10 formed on one of the laminations of the lever 59 carries a pin 'H which may be provided with an anti-friction roller if desired, and this pin functions to operate the switches hereinafter described.

The upper portion of the arm 69 is bifurcated or in effect the two outside laminations project upwardly and a pin 12 extends between them. This pin 12 carries an anti-friction roller 13 for engagement with a suitable notch 14 in a pawl 15, the purpose of which will be hereinafter described.

A spring It normally urges the arm 69 away from the core of the magnet 58, and the pin 12 and its roller into engagement with the notch '14. As illustrated in Fig. 4 one end of the spring rests over the upper part of the arm 69 and it then passes downwardly under the pivots 55 and 57 of the bell crank levers. The arrangement of the spring permits of a minimum amount of energy being expended in moving the bell crank levers from the full line locked position of Fig. 4 to the broken line position A which the bell crank levers occupy when the magnet is energized and the bomb is to be released, thus entailing the use of a minimum amount of current. Apart from the two outside laminations of the arm 59 the remaining laminations are slabbed oil as indicated at TI to provide a clean ance for the pawl 15 as will be hereinafter ap parent.

The pawl i5 is pivoted to one of the cover retaining studs 21. As heretofore stated when the parts are in the full line position of Fig. 4 or the bomb supporting position the notch 7 1 on the free end of the pawl is in engagement with the pin and roller 12, 13 on the upper end of the arm 69 of the bell crank lever 59. A link or a pair of links 18 is pivoted at one end '19 to an intermediate position of the pawl and at the other end 80 to a block 8 I.

The block BI is formed as part of a plunger 32 which has a bearing at one end in a bushing 8-3 mounted in the casing 25. A felt packing 84 may be provided'in the bushing for weather proofing purposes. The end of the plunger extending beyond the casing 25 carries an arm 85 having a toe 86 which engages the operating lever 2% of the bomb releasing mechanism.

The part of the plunger extending on the pposite side of the block 81 is surrounded by a spring 81 which is confined between the block 8! and the end wall of the casing 25 whereit takes over a positioning abutment 88. The spring 87 is surrounded by a tube 89 which acts as a guide for a spring 90 of larger diameter and which is likewise confined between the block 3! and the end wall of the casing. The two springs provide ample power to operate the bomb releasing mechanism through the medium of the lever 20. To provide for a further guide for the springs and the plunger the upper portions of the magnet retaining brackets 5|, as shown in Fig. 6 are appropriately shaped. The bracket 5| prevents lateral displacement of the magnet '50 and lugs 9! formed on the bottom wall of the casing engage the ends of the magnet core to prevent longitudinal displacement thereof.

Referring again to the toe l9 and the pin H for operating the switches it will be noted there are three sets of contacts 92, 93 and 94 separated by suitable insulation blocks 95 and as shown in Figs. 4 and 5 they are mounted as a unit which may be readily installed in or removed from the casing.

The contacts 92 might be termed normally closed contacts and their leads (not shown) control the pilot light in the bombardiers station. The contacts 93 are likewise normally closed contacts and control the circuit to the magnet 59. The contacts 94 are normally open contacts and control the circuit leading to the magnet in the next .or adjoining station.

When .the parts-:are in: the full line position of Fig. 4 or the bomb holding position the contacts 92 and 93 are closed, the pilot light in the bombardiers station is on and when a switch in the circuit controlled by closed contacts 93 is thrown the electro-magnet is energized, the parts assume the A position and the bomb is dropped, the contacts 92 and 93 remaining closed.

When the current to the magnet 50 is cut the bell crank levers 58 and 59 under the urge of the spring 16 will assume the B position of Fig. 4 or the full line position of Fig. 7. The contacts 92 and 93 will be opened, the light in the bombardiers station going out to inform him the bomb has been released and the one in the next station is ready, and the circuit has been broken to the first station. The contacts 94 are closed to prepare the circuit for the electro-magnet in the next station so that when the main switch is closed again the cycle will be repeated. The broad aspects of this system being well known it is not thought necessary to show a wiring diagram, and if desired reference may be had to my copending' application, Serial No. 515,590, filed Dec. 24, 1943.

To facilitate moving the parts back to the bomb holding position the upper surface of the pawl i5- is curved at its free end as indicated at 56. This curved portion cams against the roller 13 until the roller slips over the end of the pawl and enters its notch 14.

Fig. 7 illustrates the posiiton of the parts after the bomb has been dropped and the current has been cut to the magnet 56. It will be noted when the arms 62 of the bell crank levers are in the horizontal position of Fig. 4 the stud 64 snugly engages its seats 63 in the adjacent ends of the lever arms. Both arms will thus be kept in line with a minimum amount of friction being exerted. When the levers are moved to the position of Fig. 7 or in the reverse direction as would be the case when the magnet is energized the stud moves slightly away from its sockets or seats 63 and thus while maintaining to all intents and purposes a rigid connection between the arms for the lines of magnetic flux and for up or down movement of the arms, it positively removes the increment of friction.

Obviously the release control may be used on racks as well as shackles or it may be used on a combination rack where a series would be mounted in the same structure. In other words the release control unit is extremely versatile and may be used in any bomb release mechanism where a high speed release is desired to control the energy stored in a spring by electric control.

From the foregoing it is thought to be apparent a release unit for a bomb shackle has been provided which will function accurately and efficiently, one that may be assembled with the greatest of ease and with practically no equipment outside of a screw driver, and one in which the parts are all readily accessible after the cover has been removed so that any of the parts may be quickly removed and replacements made.

Such changes in details of construction and arrangements of parts as would occur to one skilled in the art are to be considered as coming within the spirit of the invention as set forth in the appended claims.

I claim:

l. A control unit for housing the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination,

a casing, an electro-magnet mounted in said cas,

ing, a-pair of statically balanced'bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers functioning as armatures for said electro-magnet means between the other arms of said statically balanced levers for causing them to move in unison with each other, and means releasable by one of said arms of one of said statically balanced levers for releasing the bomb holding mechanism of said shackle when said magnet is energized,

2. A control unit for housing. the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms ofeach of said statically balanced levers functioning as armatures for said electro-magnet, means interposed between the adjacent ends of the other arms of said statically balanced levers to cause said levers to move in unison with each other, and means releasable by one of the first mentioned arms of one of said statically balanced levers for releasing the bomb holding mechanism of said shackle when said magnet is energized.

3. A control unit for housing the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers function ng as armatures for said electro-magnet seats formed in the adjacent ends of the other arms of said statically balanced levers, a stud cooperating with said seats to cause said levers to move in unison with each other and means releasable by one of the first mentioned arms of one of said statically balanced levers for releasing the bomb holding mechanism of said shackle when said magnet is energized.

4. A control unit for housing the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers functioning as armatures for said electro-magnet seats formed in the adjacent ends of the other arms of said statically balanced levers, a stud cooperating with said seats to cause said levers to move in unison with each other, a spacer plate carried by the pivots of said statically balanced levers, said spacer plate functioning to aid in preventing displacement of said levers, a, head on said stud. said head being confined between said levers and said spacer plate, and means releasable by one of the first mentioned arms of one of said statically balanced levers for releasing the bomb holding mechanism of said shackle when said magnet is energized.

5. A control unit for housing the electrical mechanism, for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers functioning as armatures for said electro-magnet, means interposed between the adjacent ends of the other arms of said statically balanced levers to cause said levers to move in unison with each other,

spring means urging said armatures away from said magnet, a pawl haVlng its free end engaging one of said armatures when the parts are in the bomb holding position; and means releasable by said pawl for releasing the bomb holding mechanism of said shackle when said magnet is energized.

6. A control unit for housing the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers functioning as armatures for said electro-magnet, means interposed between the adjacent ends of the other arms of said statically balanced levers to cause said levers to move in unison with each other, spring means urging said armatures away from said magnet, a pawl having its free end engaging one of said armatures when the parts are in the bomb holding position, a rod slidably mounted in said casing, links connecting said pawl and said rod, and means operable by said rod for releasing the bomb holding mechanism of said shackle when said magnet is energized.

7. A control unit for housing the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers functioning as an armature for said electro-magnet, means interposed between the adjacent ends of the other arms of said statically balanced levers to cause said levers to move in unison with each other, a pair of normally closed switches and a normally open switch mounted in said casing, means carried by one of said statically balanced levers for opening said normally closed switches and closing said normally open switch, and means releasable by one of the first mentioned arms of one of said statically balanced levers for releasing the bomb holding mechanism of said shackle when said magnet is energized.

8. A control unit for housing the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers functioning as armatures for said electro-magnet, means interposed between the adjacent ends of the other arms of said statically balanced levers to cause said levers to move in unison with each other, a pair of normally closed switches and a normally open switch mounted in said casing, a toe formed on one of said statically balanced levers, a pin carried by said toe for opening said normally closed switches and closing said normally open switch, and means releasable by one of the first mentioned arms of one of said statically balanced levers for releasing the bomb holding mechanism of said shackle when said magnet is energized.

9. A control unit for housing the electrical mechanism for operating a bomb releasing shackle, said control unit having in combination, a casing, an electro-magnet mounted in said casing, a pair of statically balanced bell crank levers pivoted in said casing, one of the arms of each of said statically balanced levers functioning as armatures for said electro-magnet, means interposed between the adjacent ends of the other arms of said statically balanced levers to cause said levers to move in unison with each other, a

normally closed switch for controlling a circuit to a pilot light, a normally closed switch for controlling a circuit to the electro-magnet, 3, normally open switch for controlling a circuit leading to an electro1nagnet of the shackle at the next station, all of said switches being mounted as .a unit in said casing, a pin carried by one of said statically balanced levers to operate said switches, the normally closed switches remaining closed and the normally open switch remaining open when the levers are in bomb holding position and when the magnet is energized to bring said levers to bomb releasing position, and the normally closed switches being opened and the normally open switch being closed when the current to the magnet is cut, and means releasable by one of said first mentioned arms of one of said statically balanced levers for releasing the bomb holding mechanism of said shackle when said magnet is energized.

10. A bomb releasing shackle having in combination a frame provided with supporting and releasing means for a bomb, a control lever for operating said releasing means, a control unit comprising a casing mounted on said frame adjacent said control lever, a magnet mounted in said casing, an arm extending from said control unit, said arm engaging said control lever, a pair of statically balanced levers pivoted in said casing and under the influence of said magnet, a

pair of normally closed switches and a normally open switch mounted in said casing means carried by one of said statically balanced levers for opening said normally closed switches and closing said normally open switch, and connections including spring means between said statically balanced levers and said arm whereby when said 10 magnet is energized said arm under the influence of said spring means will move said control lever to operate said bomb releasing means.

11. A bomb releasing shackle having in combination a frame provided with supporting and releasing means for a bomb, a control lever for operating said releasing means, a control unit comprising a casing mounted on said frame adjacent said control lever, a magnet mounted in said casing, an arm extending from said control unit, said arm engaging said control lever, a pair of statically balanced levers pivoted in said casing and under the influence of said magnet, a normally closed switch for controlling a circuit to a pilot light, a normally closed switch for controlling a circuit to the electro-magnet, a normally open switch for controlling a circuit leading to an electro-magnet of the shackle at the next station, all or" said switches being mounted as a unit in said casing, a pin carried by one of said statically balanced levers to operate said switches, the normally closed switches remaining closed and the normally open switch remaining open when the levers are in bomb holding position and when the magnet is energized to bring said levers to bomb releasing position, and normally the closed switches being opened and the normally open switch being closed when the current to the magnet is cut, and connections between said statically balanced levers and said arm spring means whereby when said magnet is energized said arm under the influence of said spring means will move said control lever to operate said bomb releasing means.

ROSCOE I. MARKEY. 

